Modeling Wildfire Spread in Mountain Pine Beetle-Affected Forest Stands, British Columbia, Canada

Fire Ecology

Table 3 Summary statistics from the fitted ROS models, based on Equation 2.

	Model 1	P	Model 2	P	Model 3	P	Model 4c	P	Model 4
a	120		120		120		120		a
b	0.0518^t	0.025	0.0399†	<0.001	0.0801†	<0.001	0.0408†	<0.001	a
c	1.871†	0.0143	1.5		3		1.5		a
n	16		16		16		14		16
r²	0.572		0.563		0.515				0.557
AIC^b	76.716		75.024		76.718				75.204
Obs. ^c	Cook’s D	Inn.? ^d	Cook’s D	Infl.? ^d	Cook’s D	Infl.? ^d	Cook’s D	Infl.? ^d
1	0.0226		0.0452		0.0264		0.0544
2	3.4167	*	0.6976	*	0.0012		0.6031	*
3	0.0445		0.0654		0.1047		0.0587
4	0.0340		0.0594		0.0277		0.0688
5	0.1640		0.0804		0.0867		0.0786
6	0.0016		0.0043		0.0005		0.0061
7	0.0834		0.0628		0.0938		0.0592
8	0.0268		0.0131		0.0309		0.0114
9	0.0266		0.0318		0.0624		0.0274
10	0.0001		0.0002		0.0007		0.0003
11	0.1618		0.2287		0.4170	*	0.2631
12	0.1335		0.2488		0.3187	*	0.2801
13	0.0000		0.0002		0.0016		0.0011
14	0.0009		0.0031		0.0005		0.0050
15	0.0084		0.0039		0.0000
16	0.0471		0.0290		0.0043

† Indicates fitted coefficients (rather than assigned a priori).
^a Model 4 is a combination of Model 4c (for intermittent or active crown fires) and the FBP C-3 curve (for surface fires); see text for details.
^b Akaike’s Information Criterion.
^c Observations numbers; they are same as in tables 1 and 2.
^d Influential observations (*) are considered those where Cook’s Distance > 4/n, or 0.25 for the present case.